## Question

One end of a string of length 1.0 m is tied to a body of mass 0.5 kg. It is whirled in a vertical circle as shown in fig. If the angular frequency of the body is 4 rad s^{–1}, what is the tension in the strong when the body is at the topmost point *A*? Take *g* = 10 ms^{–2}.

### Solution

3 N

Speed of the body (*v*) = Rω = 1.0 × 4 = 4 ms^{ –1}.

Referring to fig, we find that, when the body is at the topmost point *A*, the tension in the string is

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